Mobile Communication System and Method for Processing Handover Procedure Thereof

1. A method for processing a handover procedure by a user equipment (UE) of a mobile communication system, the method comprising: receiving, by the UE, a radio resource reconfiguration message from a base station; recognizing, by the UE, a handover type based on information included in the received radio resource reconfiguration message, wherein the information is mobility related information, wherein the mobility related information includes each of a first parameter indicating a target physical cell identity and a second parameter indicating a new user equipment (UE) identity, and wherein the first parameter is a physical cell identity (PCI) and the second parameter is a cell-radio network temporary identifier (C-RNTI); and performing, by the UE, a first or second handover procedure according to the recognized handover type, wherein the first or second handover procedure is performed based on whether a new C-RNTI or a new PCI exists in the radio resource reconfiguration message.

2. The method of claim 1 , wherein the radio resource reconfiguration message is a handover command.

3. The method of claim 1 , wherein the information further comprises a handover type indicator.

4. The method of claim 1 , wherein the first handover procedure indicates a procedure for handover between different base stations.

5. The method of claim 1 , wherein the second handover procedure indicates a procedure for handover in the same base station.

6. The method of claim 1 , further comprising: if a transmission/reception acknowledgement information operation indicator is included in the information, starting data transmission after receiving transmission/reception acknowledgement information.

7. The method of claim 6 , wherein the transmission/reception acknowledgement information is a packet data convergence protocol (PDCP) status protocol data unit (PDU).

8. A mobile communication system, comprising: a base station configured to transmit a radio resource reconfiguration message; and a user equipment (UE) configured to receive the radio resource reconfiguration message, recognize a handover type based on information included in the received radio resource reconfiguration message, and perform a first or second handover procedure according to the recognized handover type, wherein the information is mobility related information, wherein the mobility related information includes each of a first parameter indicating a target physical cell identity and a second parameter indicating a new user equipment (UE) identity, wherein the first parameter is a physical cell identity (PCI) and the second parameter is a cell-radio network temporary identifier (C-RNTI), and wherein the UE performs the first or second handover procedure based on whether a new C-RNTI or a new PCI exists in the radio resource reconfiguration message.

9. The system of claim 8 , wherein the radio resource reconfiguration message is a handover command.

10. The system of claim 8 , wherein the information further comprises a handover type indicator.

11. The system of claim 8 , wherein the first handover procedure indicates a procedure for handover between different base stations, and the second handover procedure indicates a procedure for handover within the same base station.

12. The system of claim 8 , wherein if a transmission/reception acknowledgement information operation indicator is included in the information, the UE starts data transmission after receiving transmission/reception acknowledgement information.

13. The system of claim 12 , wherein the transmission/reception acknowledgement information comprises a packet data convergence protocol (PDCP) status protocol data unit (PDU).

14. A user equipment configured to operate in a mobile communication system, the user equipment comprising: a processor configured to receive a radio resource reconfiguration message from a base station, recognize a handover type based on information included in the received radio resource reconfiguration message, and perform a first or second handover procedure according to the recognized handover type, wherein the information is mobility related information, wherein the mobility related information includes each of a first parameter indicating a target physical cell identity and a second parameter indicating a new user equipment (UE) identity, wherein the first parameter is a physical cell identity (PCI) and the second parameter is a cell-radio network temporary identifier (C-RNTI), and wherein the first or second handover procedure is performed based on whether a new C-RNTI or a new PCI exists in the radio resource reconfiguration message.